Technical Field
This disclosure is directed to rocking piston compressors or pumps and, more specifically, to rocking piston compressors or pumps with sound dissipation qualities that result in both a quieter operation and higher efficiency at high operating duties.
Description of the Related Art
Rocking piston or reciprocating compressors generally include one or two pistons, which reciprocate within one or two cylinders respectively. Dual cylinder rocking piston compressors, for example, include a pair of valve plates that cover the two cylinders, and a pair of heads that cover the valve plates, leaving intake and exhaust chambers or spaces between the heads and valve plates. Typically, each head may include at least one intake port and at least one exhaust port. For a compressor having both cylinders working in parallel, communication between the intake chambers of each head/valve plate and between the exhaust chambers of each head/valve plate is provided by two crossover passageways or conduits. For a compressor having both cylinders working in series (or “staged operation”), communication between the exhaust chamber of the first head/valve plate portion and between the intake chamber of the second head/valve plate portion is provided by one crossover passageway or conduit. Further, some designs employ a single-piece valve plate body and some designs employ a single-piece head. The gas or air flows into the compressor though the intake and is directed into the cylinders through valved inlet ports in the valve plates. Compressed air or gas is pumped out of the cylinders through valved outlet ports in the valve plates that are in communication with the compressor exhaust.
In many rocking piston compressor applications, compressor noise is an issue. For example, oxygen concentrators typically utilize a dual-cylinder, rocking piston compressor, which must be located near the user (or patient). As a result, it is desirable to minimize the noise produced by the compressor. Of course, there are numerous other applications where rocking piston compressors are appropriate, but noise remains an issue. For example, rocking piston-type compressors are used in other medicinal applications as well as various industrial, scientific and food manufacturing applications.
Accordingly, dual-cylinder (parallel and staged operation) and single-cylinder rocking piston-type compressors are needed that are quieter than currently available designs, without compromising output, performance or efficiency.